Mycoplasma fermentans (Incognitus Strain) Cells Are Able to Fuse with T Lymphocytes

Characteristics of the fusion of Mycoplasma fermentans (incognitus strain) with cultured lymphocytes were investigated. The rate and extent of fusion were monitored continuously in an assay that measured lipid mixing on the basis of dequenching of a fluorescent probe, octadecylrhodamine (R18), incorporated into mycoplasmas. Fusion of M. fermentans was detected with CD4 + (Molt-3) cells, CD4 - (12E1) cells, and primary peripheral-blood lymphocytes. The level of fusion was relatively low (8%-12%)